【作者】 王洁；

【导师】 李传习； 刘建；

【作者基本信息】 长沙理工大学 ， 土木工程， 2017， 硕士

【摘要】 桥梁工程建设通常投资金额高、涉及面广、使用年限长,一旦发生桥梁事故,后果往往很严重。我国已建了大量的斜拉桥,如广东佛山市三水大桥、上海徐浦大桥、汕头磐石大桥、天津永和大桥等。随着斜拉桥运营年限的增加,大部分已建的斜拉桥或多或少的出现了不同程度的损伤。从现有各国已经建成的斜拉桥运营观测的实际情况来看,有不少的斜拉桥出现过如斜拉索断索等局部构件失效的情况,这样的例子不胜枚举,如:海印桥、白沙大桥、Wye桥等。斜拉桥的受力体系复杂,各个构件之间联系紧密,如果某一个关键构件失效,将会牵动其他构件。通过研究斜拉桥运营阶段局部构件失效风险,筛选出可能诱发局部构件失效的致险因子,对于保障桥梁的安全及完善桥梁全寿命风险评估都有一定的借鉴意义。目前,从国内外研究成果看来,桥梁风险评估主要研究集中在桥梁施工安全、桥梁船撞、车撞、火灾、超载、抗震等方面,以及评估方法的改进。本文针对基本没有研究斜拉桥运营阶段斜拉索断索风险评估的这个情况,以广东省佛山市三水大桥主桥斜拉桥为工程背景,应用模糊综合评价法对该桥局部构件失效风险进行评价,研究该桥在运营阶段斜拉索断索、拉力支座失效等局部构件失效的概率及损失。论文主要工作内容及步骤如下示:首先,通过建立三水大桥主桥的有限元模型,对桥梁结构进行参数分析,把可能导致桥梁事故的因素进行整理,并作为后续风险识别的依据;对各种有可能发生的桥梁风险事故进行辨识,通过参数分析计算出各种危害对结构所带来的影响;对可能引起事故的各种致险因子进行辨识,在对各种致险因子进行识别的基础上,分析和筛选出主要的致险因子,并归纳整理出桥梁风险清单。然后通过层次分析法计算各个因素的相对权重,得到可能导致斜拉索断索、拉力支座失效等致险因子的排序结果,并利用综合评价法对三水大桥使用阶段局部构件失效风险进行量化和评估。最后,根据评价结果及接受准则做出决策,如果风险等级很低则接受风险,若果风险等级高,则出具相应的风险控制办法。更多还原

【Abstract】 Bridge engineering is usually high investment,involving a wide range,long service life,once the bridge accident,the consequences are often very serious.A large number of cable-stayed bridges have been built in our country,such as the SanShui bridge of FoShan City Guangdong and the YangPu bridge of ShangHai and the QueShi bridge of ShanTou and the YongHe bridge of TianJin.With the increase of service life of cable-stayed bridge,most of the cable-stayed bridges have different degrees of damage.From the actual situation of the existing cable-stayed bridge operation observation,a lot of cable-stayed bridges have been failure.such as Stay cable lose effectiveness,Such examples could be multiplied indefinitely.The stress system of cable-stayed bridge is complex,each component is closely linked,if a key component failure will affect other components.It is of great significance to ensure the safety of the bridge that based on the study of failure risk of local members of cable stayed bridge,screening the risk factors that may cause the failure of local components.This paper is based on the main bridge of Foshan Sanshui bridge in Guangdong,study the、probability and loss of the bridge in the operation stage of cable lose effectiveness and Tension compression abutment lose effectiveness.Combined with field testing and parameter analysis and Bridge Risk Assessment Theory to obtained the list of risk factors of lead to cable lose effectiveness and Tension compression abutment lose effectiveness.And use fuzzy comprehensive evaluation method to evaluate the failure risk of the local members of the bridge.The main contents of this paper are as follows:First,Parameter analysis of bridge structure by establishing the finite element model of the main bridge of Sanshui Bridge,Sorting out the factors that may lead to bridge accidents,and as the basis for subsequent risk identification.Identify possible risk incidents,and calculate the effects of various hazards by parameter analysis.Identify various risk factors that may cause an accident,on the basis of the identification of various risk factors,analyze and screen the main risk factors,and induction the risk list.Secondly,calculate the relative weight of each factor by the analytic hierarchy process chalk up the ranking results of risk factors of cause cable lose effectiveness and Tension compression abutment lose effectiveness.Use the comprehensive evaluation method to evaluate the failure risk of local members of the bridge.Last,according to the evaluation results to make decisions,if the risk level is very low,accept the risk,if the risk level is high,issued by the corresponding risk control measures.更多还原